1/*
2 * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the author nor the names of any co-contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD$
30 */
31
32#include "namespace.h"
33#include <stdio.h>
34#include <errno.h>
35#include <pthread.h>
36#include "un-namespace.h"
37#include "thr_private.h"
38
39int	__nanosleep(const struct timespec *time_to_sleep,
40	    struct timespec *time_remaining);
41
42__weak_reference(__nanosleep, nanosleep);
43
44int
45_nanosleep(const struct timespec *time_to_sleep,
46    struct timespec *time_remaining)
47{
48	struct pthread	*curthread = _get_curthread();
49	int             ret = 0;
50	struct timespec ts, ts1;
51	struct timespec remaining_time;
52	struct timespec wakeup_time;
53
54	/* Check if the time to sleep is legal: */
55	if ((time_to_sleep == NULL) || (time_to_sleep->tv_sec < 0) ||
56	    (time_to_sleep->tv_nsec < 0) ||
57	    (time_to_sleep->tv_nsec >= 1000000000)) {
58		/* Return an EINVAL error : */
59		errno = EINVAL;
60		ret = -1;
61	} else {
62		if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
63			return (__sys_nanosleep(time_to_sleep, time_remaining));
64
65		KSE_GET_TOD(curthread->kse, &ts);
66
67		/* Calculate the time for the current thread to wake up: */
68		TIMESPEC_ADD(&wakeup_time, &ts, time_to_sleep);
69
70		THR_LOCK_SWITCH(curthread);
71		curthread->interrupted = 0;
72		curthread->wakeup_time = wakeup_time;
73		THR_SET_STATE(curthread, PS_SLEEP_WAIT);
74
75		/* Reschedule the current thread to sleep: */
76		_thr_sched_switch_unlocked(curthread);
77
78		/* Calculate the remaining time to sleep: */
79		KSE_GET_TOD(curthread->kse, &ts1);
80		remaining_time.tv_sec = time_to_sleep->tv_sec
81		    + ts.tv_sec - ts1.tv_sec;
82		remaining_time.tv_nsec = time_to_sleep->tv_nsec
83		    + ts.tv_nsec - ts1.tv_nsec;
84
85		/* Check if the nanosecond field has underflowed: */
86		if (remaining_time.tv_nsec < 0) {
87			/* Handle the underflow: */
88			remaining_time.tv_sec -= 1;
89			remaining_time.tv_nsec += 1000000000;
90		}
91		/* Check if the nanosecond field has overflowed: */
92		else if (remaining_time.tv_nsec >= 1000000000) {
93			/* Handle the overflow: */
94			remaining_time.tv_sec += 1;
95			remaining_time.tv_nsec -= 1000000000;
96		}
97
98		/* Check if the sleep was longer than the required time: */
99		if (remaining_time.tv_sec < 0) {
100			/* Reset the time left: */
101			remaining_time.tv_sec = 0;
102			remaining_time.tv_nsec = 0;
103		}
104
105		/* Check if the time remaining is to be returned: */
106		if (time_remaining != NULL) {
107			/* Return the actual time slept: */
108			time_remaining->tv_sec = remaining_time.tv_sec;
109			time_remaining->tv_nsec = remaining_time.tv_nsec;
110		}
111
112		/* Check if the sleep was interrupted: */
113		if (curthread->interrupted) {
114			/* Return an EINTR error : */
115			errno = EINTR;
116			ret = -1;
117		}
118	}
119	return (ret);
120}
121
122int
123__nanosleep(const struct timespec *time_to_sleep,
124    struct timespec *time_remaining)
125{
126	struct pthread *curthread = _get_curthread();
127	int		ret;
128
129	_thr_cancel_enter(curthread);
130	ret = _nanosleep(time_to_sleep, time_remaining);
131	_thr_cancel_leave(curthread, 1);
132
133	return (ret);
134}
135